Adapting id Tech 3 Thread

id Tech 3 is the last in the line of id Tech engines to be open source. Unfortunately while it is a passable 3D engine it lacks several components that its graphically superior successor engines (such as id Tech 4, which due to legal difficulties has not been made open source in its pure form but only as the Doom 3 source code, and even that's been mucked around with by the lawyers) have. It's coded in C rather than C++, the lighting and physics aren't much to speak of (no Carmack's reverse here, oh dear) and basically it's not the best.

So I was thinking, why not modify the engine by porting it to C++ and adding in some code from the open source Doom 3 source code release and make that into a new open source engine that is graphically superior and doesn't need a license to use? Thus giving future devs an easy and decent-looking alternative engine to use.